Thermionic device



E. A. RocKwELL 1,932,677

THERMIONIC DEV ICE Oct. 31, 1933.

Filed Oct. 13, 1951 xNvEN'roR ATTORNEY Patented Oct. 31, 1933 UNITED STATES ONIC DEVICE Edward A.

otDelaware Rockwell, Chicago, Ill., signor to Patent Engineering Corporation.

a corporation Application October 13, 1931. Serial No. 588,552

'I Claims.

This invention relates to improvements in l thermionic devices and has for an object the ity of hooks 15 carried metallic member 10, and a sec-- provision of exible means between the reentrant stem o1' such a device and the element assembly thereof.

Another object of the invention is the provision in a thermionic device of filament supports adapted to support the iilaments in deiinite and dried space relation to the envelope of the device.

.ai further object oi the invention is the provision oi an element assembly or structure in a thermionic device iiexibly mounted before insertion in the envelope and adapted to remain in xed relation to the envelope after being inserted therein regardless o! any misalignment in the mounting.

Still another object of the invention is the provision in a thermionic device of a flexible support i'or the element assembly thereof, adapted to act as an electrical conductor for one of the elements of the device.

other objects and advantages will be apparent to those skilled in the art upon perusal oi' this specification and the appended claims.

Referring to the drawing:

Figure l is a View, partly broken away, of a thermionic device constituting one embodiment o the invention;

Figure 2 is a sectional ci Figure 1;

Figure 3 is a view of a portion o! a thermionic device showing one modification of the invention; and

Figures and 5 show other modications of the invention.

The element assembly in the preferred form shown herein consists of a central metallic member i having an anode 11 supported thereon in any suitable manner, such as by a metallic cross piece 12 which may be welded to the anode 1l and to the metallic member 10. The part 12 may have one end extended downwardly to support a getter 13. A fllamentary cathode 14 surrounds the anode or plate ll. This cathode view along the line 2-2 is in the form of a zigzag filament which may be supported by any suitable means such a pluralby a glass bead 16 at the upper end oi the ond set ci hooks 17 carried by a glass bead 18 secured to the member 10 at a point below the bead 16. Viewed from above the upper hooks are preferably not in line with the lower hooks.

These hooks are of such length that their extremities nt the interiorof the glass envelope 19 when the element structure is placed therein.

(Cl- Z50-21.5)

Themember lohasatwistthereinbotween the lower bead 18 and the "press 20 o! the stem 21, and this member 10 is adapted to form a. conductor between the anode 11 and one of the prongs in the base of presently described.

Sealed into the press with the member 10 are 20 of the stem 21 along the conductors 22 and 23 to which the illament or cathode 14 is cons nected.

The member supporting the anode 11 and the beads 16 and 18 thereon supporting the upper and lower hooks and 1'7 carrying the iliament 14, comprises an element structure which is flexibly supported on 10 having the twist 24 therein. g This twist allows the element structure to move angularly with respect to the center axis of the stem in any direction, so that when the element structure is assembled into the glass envelope 19, the hooks l5 and 17 ilt the interior thereof and hold the element structure deilnitely in iixed relation thereto, and when the stem 21 is sealed into the envelope 19, any variations or inaccuracies in this process will not ai'iect this fixed relation. 80

This relation between the elements and the envelope is important in thermionic devices such as described in the cao-pending application, Serial No. 566,08, iiled September 30, 1931, by Earl L. `Koch in connection with which an outside grid 86 is used.

This construction also has a distinct advantage in that thermionic devices so constructed will stand very rough handling, it being impossible to dislocate the element assembly without breaking 90 more elements than those element strucof the invention, and in four and iive element tubes where the element structure becomes top heavy the herein described method of locating the assembly within the envelope eliminates the breakage now prevalent with these types of tubes.

After the stem 21 is sealed into the envelope 1 and the device is evacuated and sealed ofi, a base 24 may be secured thereto and the conductors are connected to the prongs thereof, two of which j are shown at'25 and 26.

In the modiiication shown in Figure 3, the central member 10a is shown as a straght metal.- lic rod, preferably oi' flexible or springy material, and while shown as one piece, it may consist of metals of different character welded together to 110 the device which will be 60 the stem by the member 70 support the element structure stem 21.

In the modification shown in Figure 4, the central member b has a portion ot its length between the lower bead 18 and the press 21 oi' the stem 20 i'ormed into a helix 27.

In the modification trai member 10c has a portion ot its length between the lower bead 18 and the press 21 of the stem 20 formed into an 8 shaped loop 28.

Many other modiilcations may be made by those skilled in the art without departing from the invention. y

While no grid is shown in the drawing, the embodiment of the device as shown in Figure 1 contemplates the use ot a grid iltting the outside of the glass envelope. This grid may be in the i'orm of a sleeve or it may be in the form of a cap and it may be made of any suitable material such as is described in the co-pending application above referred to, and with the grid omitted exibly on the the device may be used as a diode or as a rectier.

What is claimed is:

l. In a thermionic device, an element structure including an anode and cathode, a stem having said structure ilexibly supported thereon, and an enclosing envelope adapted to be assembled therewith, the interior walls of the envelope contacting with and laterally positioning said structure therein.

2. In a thermionic device, an element structure including an anode and cathode said cathode being supported on said structure by radial members, and a sealed envelope enclosing said structure and having its inner wall contacting with said members thereby holding said lament in denite space relation to said wall.

3. In a thermionic device, an element structure including a filament supported by two groups of radial members spaced apart, a sealed envelope shown in Figure 5, the cen- -to the wall of said envelope enclosing said structurey and having its inner wall contacting with some` of said members thereby supporting said structure and holding said niament in dennite space relation to said wall, a reentrant stem in said envelope, and a flexible member between said element structure and said stem. l

4. In a thermionic device, a sealed glass enve lope having a reentrant stem, and an element structure including radial members within the envelope flexibly supported by said stem and held in fixed relation to the inner wall of the envelope by said members.

5. In a thermionic device, an element structure including a plate and a iilament, a plurality of members above and below said plate extending beyond the' outer diameter thereof and adapted to support the filament thereabout, and a 'glass envelope surrounding said structure and having its inner wall contacting with said members thereby retaining the elements oi' said structure in fixed relation thereto.

6. In a thermionic device, an enclosing envelope having a reentrant stem, a flexible member passing through said stem in sealed relation thereto, an anode secured to said member, supports secured to said member above and below said anode, and a cathode on said supports surrounding the anode and held in xed space relation thereby.

l 7. In a thermionic device, an enclosing envelope having a reentrant stem, a exible member passing through said stem in sealed relation thereto, an anode secured to said member, filament supports-secured to said member and having radial arms with their outer ends contacting with said envelope, and a filament supported by said arms and disposed between the anode and the inside wall of said envelope.

EDWARD A. RocKWEu.. 

